The invention relates to a non-aqueous method of preparing an improved silica supported hydrotreating catalyst. Silica supported hydrotreating catalysts, when prepared by conventional aqueous pore-filling impregnation with catalytically active metals, tend to have very poor activity compared to corresponding alumina based catalysts. This is thought to be because the metal oxides (MoO.sub.3, NiO, CoO) react very weakly with the support, and thus are very poorly dispersed on the support.
Potentially, silica based hydrotreating catalysts should perform well in treating residual oil feedstocks. Silica based catalysts should be less prone to coke formation than alumina based catalysts because of the lower acidity of silica. Since coke depositon is a major catalyst deactivator in such applications, an active and stable silica based catalyst could have an enormous impact on hydrotreating such feedstocks.